This invention relates to railroad couplers and, more particularly, to a hard-facing deposit of weld material upon the bottom wall of a coupler shank to eliminate the need and disadvantages associated with wear plates fastened onto the coupler shank.
The most common type of railroad coupler is a Type E railroad coupler having a horizontal key passed through a slotted opening in the side walls of the coupler. Other known forms of couplers include an F-type and an E/F-type wherein a vertical pin is passed through an opening in the shank of the coupler. There are many variations to these known forms of couplers but each such coupler is associated with a coupler carrier that engages the shank portion of the coupler member. The cast steel construction of the coupler shank is extremely vulnerable to wear due to impact and abrasion at the area where the coupler shank contacts the usual coupler carrier or carrier wear plate. These known forms of couplers are presently provided with a wear plate having a hardness within the range of 341-415 Brinell Hardness Number. The wear plate is attached to the shank of the coupler by beads of weld at the side edges of the plate. In E/F and E-type couplers, the carrier is stationary while in F-type couplers, the carrier is resiliently supported by springs.
The use of a wear plate on coupler shanks to protect them in service has proven to be highly unsatisfactory. The wear plates on a large number of coupler shanks wear out within 1-3 years of service time. As the thickness of the wear plate is reduced in excess of one-half of its original thickness, the plate cracks and breaks into two or more pieces because of severe impact loading. These pieces of wear plate break loose from the coupler shank and fall onto the track roadbed whereby the coupler shank is left unprotected and the wear on the cast steel material thereof is extremely rapid. Furthermore, the use of wear plates is unsatisfactory because a relatively large number of wear plates comes loose from the coupler shank and is lost either due to a failure of the plate material at the edges along the weld beads or a failure of the welds. The coupler shanks are again left unprotected and wear to the point of condemning limit whereby failure can occur.